I’m not aware of any over 12’ but I have heard of people running 220 well pumps with cords as long as 100 feet. It depends on the wire gauge of your 30 amp circuit andthe gauge of your extension cord and the motor size on the Unisaw.

I know someone who said he could run a 100 ft. 220 extension cord and stay within limitsas long as the wire diameter on the extension cord was 8 gauge.

you can put whatever plug on the end of a cord that you want. At this Length and power requirment I would say you would need a GOOD 12AWG cord. Not just the cheapest peice of shit out there. I’m sure you could buy a 220v cord. Or I’d just goto an electrical supplier and buy 100’ of 12-3 cord and ask for a male and female 220v cord cap

10/2 will not work you nee 2 hots a neutral and a ground. I would go with 8/3 personal NEC calls for 10/3 for runs up to 150 feet. this will be an extension cord so you want to factor in the run from the panel to the outlet and the cord from the tool as well. 10/2 no longer meets NEC standerds. im a fan of twist lock conector for the ends. just be aware the is not going to be cheap no mater witch way you go rv cords are a poor choice for it would be over kill and 10/3 or 10/4 cable is about 250 bucks for 150 foot roll. while i would say 8/3 is the way to go i think you would fine with 10/3 or 4 if you find your under 150. btw i keep saying 10/3 or 4 because cord which is what you want is often sold as 10/4 rather then 10/3. ultimately you need the cord to have 4 wires.

-- I buy tools so i can make more money,so ican buy more tools so I can work more, to make more money, so I can buy more tool, so I can work more